fix: tcp client memory leaks #10286

packages/microservices/client/client-tcp.ts

@@ -108,6 +108,13 @@ export class ClientTCP extends ClientProxy {
     this.isConnected = false;
     this.socket = null;
     this.connection = undefined;
+    if (this.routingMap.size > 0) {
+      const err = new Error('connection to server closed');
+      for (const callback of this.routingMap.values()) {
+        callback({ err });
+      }
+      this.routingMap.clear();
+    }
   }
 
   protected publish(

packages/microservices/test/client/client-tcp.spec.ts

@@ -154,9 +154,15 @@ describe('ClientTCP', () => {
     });
   });
   describe('close', () => {
+    let routingMap;
+    let callback;
+
     beforeEach(() => {
-      (client as any).socket = socket;
+      routingMap = new Map<string, Function>();
+      callback = sinon.spy();
+      routingMap.set('some id', callback)(client as any).socket = socket;
       (client as any).isConnected = true;
+      (client as any).routingMap = routingMap;
       client.close();
     });
     it('should end() socket', () => {
@@ -168,6 +174,16 @@ describe('ClientTCP', () => {
     it('should set "socket" to null', () => {
       expect((client as any).socket).to.be.null;
     });
+    it('should clear out the routing map', () => {
+      expect((client as any).routingMap.size).to.be.eq(0);
+    });
+    it('should call callbacks', () => {
+      expect(
+        callback.calledWith({
+          err: new Error('connection to server closed'),
+        }),
+      ).to.be.true;
+    });
   });
   describe('bindEvents', () => {
     it('should bind error event handler', () => {